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    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>
    <script>
        var num = 10;
        var obj = {
            num: 20
        }
        obj.fn = (function (num) {
            this.num = num * 3;
            num++; //61
            return function (n) {
                this.num += n;
                num++;
                console.log(num)
            }
        })(obj.num)
        var fn = obj.fn
        fn(5)   //22
        obj.fn(10)  //23
        console.log(num, obj.num) // 65 30
    </script>
</body>

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